Campbell's second serious modification to the Bluebird
was made before this attempt. He reverted to using
a radiator in the normal place in front of the engine,
but contained it in a separate housing outside the
bonnet covering the engine, so that the cooling air
did not enter the engine compartment, but rushed
through the radiator only.
The transmission was also
moved to one side and the driver sat alongside the
propeller shaft, thus making the car even lower and
less resistant to wind.
The tail was also changed
again and a larger stabilising directional fin used.
Even more power was found by substituting a Schneider
Trophy supercharged Napier engine for the earlier
Lion type.
This gave 1,350 horsepower at 3600 rpm,
compared with the 900 horse-power of the un-supercharged
engine. .
After its 1931 victory the Bluebird was modified
once again in the quest for a few more miles per
hour.
This time the changes were less drastic, a
slight increase in engine power and an improvement
in the shape of the fairing round the front-mounted
radiator.